Electric fuse



Dec. 10, 1929. w. H. HUMPHREYS Er Al. 1,739,309

ELECTRIC FUSE Filed Feb. 28, 1928 'imi 3 9 70 7 l 6 70 .9 72 73 III ATTU/CNE YS Patented Dec. I, 19429 UNITED STATES PATENT oli-FICE WILLIAMH. HUMPHREYS, or YoNxEns, Ann WILLIAM J. PoLLoex, or Baonxy NEW Yom:

ELECTRIC y'isusE' Appiication filed February 28, 1928. Serial No.257,598.

This invention relates to improvements in electric fuses, and hasparticular reference to a fuse of the type employed in electric circuitsfor the purpose of protecting the same against overloads.

An object of the invention is to provide ani' improved fuse of simple,practical and inexpensive construction wherein the fusible elementemployed may be easily and quickly removed and replaced.

Another object is to provide the body of the fuse with a tapered boreextending the entire length thereof and to utilize a similarly shapedplug to secure or wedge a fusible element in the bore, said plugprojecting beyond the ends of the body, when the fusible element issecured in position, so that by tapping the smaller end of the plug thesame may be loosened preliminary to its withdrawal from said body andsubsequent removal of the fusible element.

The above and other objects will appear more clearly from the followingdetailed description, when taken in connection with the accompanyingdrawing, which illustrates a preferred embodiment of the inventive idea.

In the drawingn Figure 1 isa side elevation of the fuse constructed inaccordance with the invention;

Figure 2 is an enlarged longitudinal section thereof;

- Figure 3 Figure 2;

Figure l is an end elevation; and Figure 5 is a perspective view of thefusible element.

Referring more particularly to the accompanying drawing, the numeral 6indicates the body ofthe fuse which is made of any suitable 4oinsulating material, such as 4vulcanized fibre or the like. This body iscylindrical in crosssection and is provided with a longitudinal bore 7extending the entire length of the body and of slightly taperedformation throughis a section on Vthe line 8--3 of V out. The taperingof the bore may, however,

be dispensed with. Eachend of the body 6 has mounted thereon anelectricterminal or head 8 recessed at its end to receive the adj acent end ofsaid body. To secure the terminals 8 to the body, the inner end of eachterminal may be inturned, as indicated at 9, to extend into an annulargroove 10 formed in said body. Each terminal is also provided with acentral tapered opening 11 aligned with the bore in said body.

The fusible element 12 is of a standard type andwhen inserted intoposition in the body 6 its. ends will engage the terminals 8 so as tocomplete the electric circuit. The ends of the element 12 may projectbeyond the ends of the terminals and, in order to prevent shifting ofthe element in the body, when securing the former in position, the kendof said element adjacent `the larger end of the bore 7 may be bentlaterally, as indicated at 13, and engaged with the terminal so as toform a stop which limits the movement of said element 12 towardthe otherend of the body.

To fix the fusible element 12 in position` with its ends in contact withthe terminals 8,

there is provided an insulated plug 14 tapered longitudinally throughoutits length and capable of insertion into the bore of the body. i

ln so doing, the plug willwedge the element 12 in position, as shown,and cause the same to assume a cross-sectional contour conforming tothose of the body and terminal members thereby securing intimate Contacttherewith, it being understood that said element 12 is made of malleablemetal. The plug 14 is longer than the combined lengths of the body 6 andterminals 8 so that the ends of the plug` will project beyond` saidterminals when the plug is in wedging position. Thus said ends areeasily accessible either for the purpose of striking the larger endthereof to increase lthe wedging action or for loosening the plug bytapping upon the smaller end. It is obvious that the latter operationcan be easily and quickly accomplished in the event of the fusingof theelement 12, whereupon the defective element may be extracted and a newone fixed in its place.

`What is claimed is:

1. An electric fuse including an open ended body ofinsulating materialhaving a bore therethrough, terminal members carried by the ends of saidbody, a fusible element contacting-the wall of said bore and engagingsaid terminal members, and a tapered insulated plug extending throughsaid bore and werliging Isaid fusible element against said wa l.

2. An electric fuse including an insulated body having a bore extendingthe entire length thereof, terminal membersat the ends of saidbodyhaving openings aligned With said bore, a fusible element extending thelength of said bore and having its ends engaged with said terminal'members, and an insulated plug projecting through the openings in saidterminal members and said bore to secure said fusible element inengagement with said members.

3. An electric fuse .including an insulated body having atapered'longitudinal bore extendingits entire length, end terminalmembersfsecured to said body and having tapered openings aligned Withsaid bore, a fusible element extending through said bore and having itsends engagedfwith saidterminal members, and an insulated tapered plugprojecting through said openings and bore to engage said fusible elementand Wedge it into intimate Contact with said terminal members, the endsof saidplugextending outwardly beyond the outer ends of said'terminalmembers.

4. An electric fuse including an insulated body having a bore extendingtherethrough, and terminal members having tapered openings-the Walls ofwhich are aligned with and form continuation of said-bore, a fusibleelement extending through and contacting the Walls of said openings, anda tapered plug projecting through said bore and openings to bind saidfusible element against the Walls ofthe latter.

5. An elec-trio fuse of the cartridge type including an insulated bodyhaving a tapered bore, terminalmembers at the ends of said body, afusible element extending through theborein said body and engaged withsaid terminal members, and a tapered plug in said bore forl Wedging-saidfusible element against the-wall thereof, the ends of said plugprojecting outwardly beyond saidterminal members andbeing-exposed topermit tapping at either end when removing or Wedging in positionthefusible element.

Intestimony whereof We have allixed our signatures.

WILLIAM II. HUMPHREYS. WILLIAM J. POLLOCK.

